The present invention relates to apparatus and methods for displaying or making sensible a symbol or a mark, in particular in cases where the symbol or mark is associated with an encoded message.
Systems for displaying a symbol on a television display are well known in the art.
U.S. Pat. No. 3,928,845 to Clark describes a character generator system suitable for use in a television broadcast controller.
U.S. Pat. No. 5,253,067 to Chaney et al describes a system to allow a user to select preprogrammed labels for widely used television networks.
Japanese published application 57-65974 describes a character multiplex broadcast TV receiver having a memory for displaying a symbolic pattern representing a concealed display.
Systems for scrambling a television transmission are also well known in the art. The terms xe2x80x9cscramblexe2x80x9d and xe2x80x9cencodexe2x80x9d, in their various grammatical forms, are used interchangeably throughout the present specification and claims to refer to any method suitable for scrambling or encoding a television transmission. The terms xe2x80x9cdescramblexe2x80x9d and xe2x80x9cdecodexe2x80x9d, in their various grammatical forms, are similarly used interchangeably throughout the present specification and claims to refer to any method suitable for rendering a scrambled or encoded television transmission suitable for viewing. Many such methods are known in the art; examples of methods in wide use include xe2x80x9ccut-and-rotatexe2x80x9d, described, for example, in U.S. Pat. No. 4,070,693 to Shutterly, and DES encryption, as described below.
One system for scrambling a television data stream is described in U.S. Pat. Nos. 5,282,249 and 5,481,609, both to Cohen et al. Scrambled television transmissions described in the Cohen et al. patents include both scrambled data representing television signals and coded control messages, also known in the art as ECMs. The ECMs of Cohen et al. include, in a coded form, data necessary for generating a control word (CW) which may be used to descramble the scrambled data representing television signals.
Data necessary for generating a control word is known in the prior art to take many different forms and may include, in general, at least any of the following: a control word; an encrypted control word which is intended to be decrypted before use, and a seed to a generating function such as, for example, a one-way function which generates the control word upon input of the seed. Throughout the present specification and claims the terms xe2x80x9ccontrol word generating informationxe2x80x9d and xe2x80x9cCW generating informationxe2x80x9d are used interchangeably to designate data necessary for generating a control word in any appropriate form, as described above.
While the two patents to Cohen et al. describe an analog system, that is, a system in which analog television data streams are broadcast to television sets, it is appreciated that similar ECM methods may also be used for digital television data streams. Generally, the scrambling techniques used for scrambling analog television signals such as, for example, the well known xe2x80x9ccut-and-rotatexe2x80x9d technique, are chosen for their applicability to analog signals. In scrambling of digital television signals other scrambling techniques, well-known in the art, are used, the techniques being more appropriate to digital signals such as, for example, applying the well-known DES algorithm to the digital television signals.
A typical prior art system for scrambling and descrambling a television transmission is shown in FIG. 1. In the prior art system of FIG. 1, a removable security element such as a smart card is used to derive a CW from CW generating information included in an ECM and to supply the CW to a decoder for use in descrambling a scrambled television signal.
Methods of transmitting a scrambled digital signal, including ECMs, are well known. The prior art system of FIG. 1 may use a composite signal, that is, an analog or digital signal including more than one component, typically including both a scrambled television signal and ECMs. Prior art references which discuss examples of this type of signal include the following: DVB ETR289, xe2x80x9cDigital Video Broadcasting (DVB): Support for use of scrambling and conditional access (CA) within digital broadcasting systemsxe2x80x9d; and DVB SIM061, xe2x80x9cTechnical specification of DVB-Simulcryptxe2x80x9d, Apr. 1 1997.
Other documents relating to broadcasting of digital information include the DVB Specification for Data Broadcasting, document SI-DAT 360 (TM 1779), Feb. 12 1997; and ATSC Digital Television Standard, document A54, October 1995 and subsequent editions.
Other methods of transmitting a scrambled digital signal, particularly useful in a case where the signal includes sub-signals encoded according to various different methods, are described in xe2x80x9cCommon Interface Specification for Conditional Access and other Digital Video Broadcasting Decoder Applicationsxe2x80x9d, DVB document A017, May 1996 and subsequent editions; and in xe2x80x9cCommon Interface Specification for Conditional Access and other Digital Video Broadcasting Decoder Applicationsxe2x80x9d, CENELEC EN0221:1997.
The disclosures of all references mentioned above and throughout the present specification are hereby incorporated herein by reference.
The present invention seeks to provide an improved apparatus and methods for displaying or making sensible a symbol or a mark, in particular in cases where the symbol or mark is associated with an encoded message. In a preferred embodiment of the present invention, a symbol or mark is displayed on a display, particularly on a television display. It is appreciated that a mark, such as a trademark, may be sensible to a sense other than vision, and that the present invention is not limited in its applicability to visible marks.
The apparatus and method of the present invention are particularly applicable to encoded data systems, such as encoded data storage systems and encoded data transmission systems. One particularly well-known example of such systems is encoded television systems. Throughout the present specification and claims, encoded television systems are often discussed by way of example, without limiting the generality of the present invention. Other typical applications of the present invention include, but are not limited to the following: other encoded broadcast systems, such as encoded data broadcast systems; and non-broadcast systems, such as systems for playing back a recording, particularly systems for playing back an encoded recording.
In encoded television systems, it may be desirable to cause elements of the system which are responsible for decoding to display a symbol on a television display at a particular time. For example, it may be desirable to display a symbol, such as a trademark, associated with a vendor or with a product or service supplied by a vendor at the time of a sale or offer for sale of a product or service. In the present specification and claims, the terms xe2x80x9csymbolxe2x80x9d, xe2x80x9cmarkxe2x80x9d, and xe2x80x9ctrademarkxe2x80x9d are used interchangeably to refer to any sensible emblem, token, or sign, particularly of the kinds suitable for use as a trademark.
While the various embodiments of the present invention are generally described below with reference to display of a symbol or mark, it is appreciated that the symbol or mark may be provided as an output and not directly displayed, and the symbol may or may not be further processed, including processing for display, after being produced by the present invention.
It may further be desirable to associate such a symbol with the decoding of encoded television signals in such a way that the decoding equipment is required to supply the symbol for display in order to ensure proper decoding of the encoded signal.
There is thus provided in accordance with a preferred embodiment of the present invention a symbol-display subscriber unit for use with a broadcast system, the broadcast system including a headend and a network operative to transmit a composite signal from the headend to a multiplicity of subscriber units, the composite signal including an encoded broadcast signal encoded in accordance with a plurality of control words (CWs) and a plurality of encryption control messages (ECMs), each of the plurality of ECMs being associated respectively with one of the plurality of CWs and including CW generating information, the multiplicity of subscriber units including the at least one symbol-display subscriber unit, the symbol-display subscriber unit including a receiver receiving the composite signal from the network, security apparatus in operative engagement with the receiver, the security apparatus receiving each of the plurality of ECMs from the receiver and generating the associated CW from the CW generating information included within each the ECM, and a decoder for decoding the encoded broadcast signal for display on a display device, the decoder receiving the encoded broadcast signal from the receiver and receiving the CW from the security apparatus, wherein the security apparatus supplies symbol display information to the decoder, and the decoder provides a symbol to the display device for display thereon, the symbol being based, at least in part, on the symbol display information.
There is also provided in accordance with another preferred embodiment of the present invention a broadcast system including a headend, a network operative to transmit signals from the headend to a multiplicity of subscriber units including at least one symbol-display subscriber unit, the symbol-display subscriber unit including a receiver receiving from the network a composite signal including an encoded broadcast signal encoded in accordance with a plurality of control words (CWs), and a plurality of encryption control messages (ECMs), each of the plurality of ECMs being associated respectively with one of the plurality of CWs and including CW generating information for generating the associated CW, security apparatus in operative engagement with the receiver, the security apparatus receiving each of the plurality of ECMs from the receiver and generating the associated CW from the CW generating information included within the ECM, and a decoder for decoding the encoded signal for display on a display device, the decoder receiving the encoded signal from the receiver and receiving the CW from the security apparatus, wherein the security apparatus supplies symbol display information to the decoder, and the decoder provides a symbol to the display device for display thereon, the symbol being based, at least in part, on the symbol display information.
Further in accordance with a preferred embodiment of the present invention the security apparatus includes removable security apparatus in removable operative engagement with the receiver.
Still further in accordance with a preferred embodiment of the present invention the removable security apparatus includes a smart card.
There is also provided in accordance with another preferred embodiment of the present invention security apparatus for use with a symbol-display subscriber unit of a broadcast system, the broadcast system including a headend and a network operative to transmit signals from the headend to a multiplicity of subscriber units including at least one the symbol-display subscriber unit, the symbol-display subscriber unit including a receiver receiving from the network a composite signal including an encoded broadcast signal encoded in accordance with a plurality of control words (CWs) and a plurality of encryption control messages (ECMs), each of the plurality of ECMs being associated respectively with one of the plurality of CWs and including CW generating information for generating the associated CWs, the security apparatus being operatively engageable with the receiver and with a decoder operative to decode encoded signals using at least one CW and to provide a symbol to a display device based on symbol display information, the security apparatus including a CW generation unit receiving each of the plurality of ECMs from the receiver and generating the associated CW from the CW generating information included within the ECM, and a symbol display information unit for supplying the symbol display information to the decoder.
Further in accordance with a preferred embodiment of the present invention the security apparatus includes a symbol display information storage area for storing the symbol display information.
Still further in accordance with a preferred embodiment of the present invention at least one of the plurality of ECMs includes the symbol display information.
Additionally in accordance with a preferred embodiment of the present invention the CW includes the symbol display information.
Moreover in accordance with a preferred embodiment of the present invention the CW generating information includes a seed to a generating function for generating a CW.
Further in accordance with a preferred embodiment of the present invention the symbol is based, at least in part, on symbol display information included within at least two ECMs.
Still further in accordance with a preferred embodiment of the present invention the symbol display information includes a representation of the symbol.
Additionally in accordance with a preferred embodiment of the present invention the symbol display information includes generating information for generating the symbol.
Moreover in accordance with a preferred embodiment of the present invention at least one of the plurality of ECMs includes control information for controlling display of the symbol.
Further in accordance with a preferred embodiment of the present invention the symbol display information includes symbol display instructions, and the decoder executes the symbol display instructions.
Still further in accordance with a preferred embodiment of the present invention the decoder is operative to decode the encoded broadcast signal based, at least in part, on the symbol display information.
Additionally in accordance with a preferred embodiment of the present invention the symbol includes a trademark.
Moreover in accordance with a preferred embodiment of the present invention the broadcast system includes a television broadcast system, and the network includes a television network, and the encoded broadcast signal includes an encoded television signal.
There is also provided in accordance with another preferred embodiment of the present invention encoded information including symbol display information, wherein the symbol display information includes information for decoding the encoded information.
There is also provided in accordance with another preferred embodiment of the present invention a method for producing a symbol, the method including decoding encoded information based, at least in part, on symbol display information, and producing a symbol based, at least in part, on the symbol display information.
Further in accordance with a preferred embodiment of the present invention the encoded information includes an encoded transmission.
Still further in accordance with a preferred embodiment of the present invention the method also includes displaying the symbol on a display.
Additionally in accordance with a preferred embodiment of the present invention the method includes presenting the symbol on a virtual reality device.
Moreover in accordance with a preferred embodiment of the present invention the method includes presenting the symbol in a manner which is sensible to at least one human sense.
Further in accordance with a preferred embodiment of the present invention the method includes retrieving the symbol display information from a symbol display information storage area.
Still further in accordance with a preferred embodiment of the present invention the method also includes receiving an encryption control message (ECM) including the symbol display information.
There is also provided in accordance with another preferred embodiment of the present invention a method for decoding encoded information, the method including receiving the encoded information, and decoding the encoded information based, at least in part, on symbol display information.
Further in accordance with a preferred embodiment of the present invention the encoded information includes an encoded transmission.
Still further in accordance with a preferred embodiment of the present invention the encoded information includes the symbol display information.
Additionally in accordance with a preferred embodiment of the present invention the method also includes receiving decoding information, wherein the decoding information includes the symbol display information.
There is also provided in accordance with another preferred embodiment of the present invention a method for displaying a symbol on a display within a television system, the method including transmitting an encoded television signal, transmitting a plurality of encryption control messages (ECMs) each including CW generating information for computing a control word (CW) for decrypting the encoded television signal, at least one of the plurality of ECMs also including symbol display information, computing the CW from the CW generating information, and sending the CW and the symbol display information to a decoder.
There is also provided in accordance with another preferred embodiment of the present invention a symbol-display decoding unit for use with encoded information, the encoded information including an encoded information signal encoded in accordance with plurality of control words (CWs) and a plurality of encryption control messages (ECMs), each of the plurality of ECMs being associated respectively with one of the plurality of CWs and including CW generating information, the symbol-display decoding unit including receiving apparatus for receiving the encoded information, security apparatus in operative engagement with the receiving apparatus, the security apparatus receiving each of the plurality of ECMs from the receiving apparatus and generating the associated CW from the CW generating information included within each ECM, and a decoder for decoding the encoded information signal, the decoder receiving the encoded information signal from the receiver and receiving the CW from the security apparatus, wherein the security apparatus supplies symbol display information to the decoder, and the decoder provides a symbol in a format suitable for further processing, the symbol being based, at least in part, on the symbol display information.
Further in accordance with a preferred embodiment of the present invention the symbol-display decoding unit also includes data playback apparatus for supplying the encoded information to the receiving apparatus.
Still further in accordance with a preferred embodiment of the present invention the symbol-display decoding unit also includes virtual reality apparatus for receiving the symbol from the decoder and for providing a virtual reality display of the symbol.
Additionally in accordance with a preferred embodiment of the present invention the security apparatus is adapted to receive at least one conditional access (CA) module, the at least one CA module being operative to receive each of the plurality of ECMs from the security apparatus, generate the associated CW from the CW generating information included within each the ECM, and supply the symbol display information to the security apparatus.
Moreover in accordance with a preferred embodiment of the present invention the at least one CA module includes a plurality of CA modules.
Further in accordance with a preferred embodiment of the present invention only one of the plurality of CA modules provides the symbol display information for each of the plurality of ECMs.
Still farther in accordance with a preferred embodiment of the present invention more than one of the plurality of CA modules provides the symbol display information for at least one of the plurality of ECMs.
There is also provided in accordance with another preferred embodiment of the present invention a symbol-display decoding method for use with encoded information, the encoded information including an encoded information signal encoded in accordance with plurality of control words (CWs) and a plurality of encryption control messages (ECMs), each of the plurality of ECMs being associated respectively with one of the plurality of CWs and including CW generating information, the method including receiving the encoded information, receiving each of the plurality of ECMs and generating the associated CW from the CW generating information included within each ECM, and decoding the encoded information signal, the decoding step including receiving the encoded information signal from the receiver, and receiving the CW from the security apparatus, and supplying symbol display information for providing a symbol in a format suitable for further processing, the symbol being based, at least in part, on the symbol display information.